爆破扰动下露天矿边坡岩体力学参数确定

 在矿山巷道工程和边坡工程稳定性分析中,岩体力学参数选取会对结果产生重大影响。通过现场大型原位试验方法可以确定出符合工程实际的岩体力学参数,但存在工程浩大、费用高昂,受到多种环境和技术条件限制。一般采用Hoek-Browm准则对室内岩块试验获得的力学参数进行工程处理,常用的Hoek-Brown准则在处理边坡岩石力学参数都是忽略爆破震动对露天矿边坡的影响,而爆破扰动是影响稳定性和岩体力学参数的主要因素。利用非线性方程来表征受扰动修正系数K_m、K_s与完整性系数K_v之间的关系,建立了Hoek-Brown准则经验参数m_b、s的一种改进取值方法。以新疆东戈壁露天矿东边坡为例,采用Hoek-Brown准则爆破扰动下的修正公式及前人公式进行分析计算,结果表明,由该方法确定的介于扰动和未扰动之间的岩体力学参数更符合实际。

Determination of Mechanical Parameters of Slope Rock Masses Under Blasting Disturbance

The selection and the determination of mechanical parameters are closely related with the stability analysis of laneway and slope in mining engineering. The spot test method to obtain mechanical parameters of rock mass based on the engineering practice is restricted by many environment conditions and technique conditions and is also very costly. Because the blasting disturbance is the most important factor influencing the slope stability for a practical open-pit slope, it should be taken into consideration in the determination of mechanical parameters of slope rock mass. In general, this factor is often ignored in the Hoek-Brown standards for processing the results of indoor rock testing in line with the actual conditions. To address this problem, the nonlinear equation is applied to obtain the relationship between the modified coefficient under disturbance and the integrity coefficient. In this paper, the modified expressions of Hoek-Brown strength criterion, in consideration of the blasting disturbance, are applied to the east slope of the East Gebi open-pit. It is shown that the method in this paper gives good results.